Sat on extremely noncompliant capybara? (6)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

RODE (sat on a horse or a bicycle, for example) + end letters (extremes) of N [oncomplian] T . Definition by example. It’s the largest surviving species of rodent (about 4 feet long), native to South America, but I expect it would be noncompliant if you tried to sit on it.